The present invention generally relates to the decontamination of solid materials, and more particularly to the treatment of contaminated soil, gravel, sand, and other solid compositions in order to remove hydrocarbon contaminants therefrom.
Increased demand for petroleum and chemical products has resulted in the development of extensive and widespread production facilities. In the petroleum industry, exploration and production facilities are often developed on a large scale in remote areas. Many regions in which the production of petroleum and chemical products occur are environmentally sensitive. The discharge of organic hydrocarbons and related by-products can therefore create an adverse environmental impact, especially with respect to the contamination of soil, silt, clay, sand, gravel, and the like. For example, the contamination of soil with petroleum products (e.g. oil, refined fuels, and similar materials) presents significant containment and decontamination problems. One problem of particular concern involves the need to treat substantial amounts of contaminated materials (e.g. soil) in a rapid and effective manner while avoiding the use of other, potentially harmful chemical agents.
Many attempts have been made to treat large volumes of contaminated solid materials (e.g. soil contaminated with oils and other petroleum products). For example, prior methods involved the incineration of contaminated materials, as well as the burial thereof. These methods either produce additional contaminants (e.g. air pollution in the case of incineration) or result in long-term disposal problems when the contaminated solids are buried. A need therefore remains for a remediation/decontamination system which is able to treat large amounts of solid materials to remove hydrocarbon contaminants therefrom. It is important that the selected treatment process be capable of producing treated materials which may be released into the environment without adverse consequences. It is also important that the selected treatment process accomplish the foregoing goals without using environmentally harmful chemical agents. The present invention as described herein satisfies these goals and enables the removal of hydrocarbon contaminants from solid materials in an environmentally conscious manner while avoiding the problems described above. Accordingly, the invention represents an advance in the art of waste treatment and environmental remediation as discussed in detail below.